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121.
Samuel J Atkinson Aleksander M Gontarczyk Abdullah AA Alghamdi Tim S Ellison Robert T Johnson Wesley J Fowler Benjamin M Kirkup Bernardo C Silva Bronwen E Harry Jochen G Schneider Katherine N Weilbaecher Mette M Mogensen Mark D Bass Maddy Parsons Dylan R Edwards Stephen D Robinson 《EMBO reports》2018,19(7)
Integrin β3 is seen as a key anti‐angiogenic target for cancer treatment due to its expression on neovasculature, but the role it plays in the process is complex; whether it is pro‐ or anti‐angiogenic depends on the context in which it is expressed. To understand precisely β3's role in regulating integrin adhesion complexes in endothelial cells, we characterised, by mass spectrometry, the β3‐dependent adhesome. We show that depletion of β3‐integrin in this cell type leads to changes in microtubule behaviour that control cell migration. β3‐integrin regulates microtubule stability in endothelial cells through Rcc2/Anxa2‐driven control of active Rac1 localisation. Our findings reveal that angiogenic processes, both in vitro and in vivo, are more sensitive to microtubule targeting agents when β3‐integrin levels are reduced. 相似文献
122.
Behrooz Shojaee Sadi Mansour Bayat Parviz Tajik Seyed Jamal Hashemi 《Saudi Journal of Biological Sciences》2018,25(1):171-177
The specific immune-reaction between the anti-citrinin antibody immobilized on the surface of magnetic/silica core–shell (MSCS) and the citrinin–Rho123–BSA conjugate brings the Rho123 fluorophore as an acceptor and the QDs as a donor in close spatial proximity and causes FRET for occurring upon photo-excitation of the QDs. The novelties of this study include: (1) immobilization of the MSCS; (2) large amount of the immobilized QDs, and (3) immobilization of a large amount of Rho123 on the BSA macromolecule. Cd/Te QDs were synthesized by the simultaneous reduction of cadmium chloride and tellurium in the presence of sodium borohydride. Magnetic nanoparticles were synthesized using FeSO4 and FeCl3. The prepared magnetic nanoparticles shelled by silica using tetraethoxysilane in the presence of ammonia. Transmission electron microscopy (TEM) analysis was used for investigating shape and monodispersity of the nanoparticles. EDC/NHS was used as a cross linking agent for immobilization of the QDs, conjugation of citrinin to amino groups of BSA, labeling of BSA with Rho123 and also for immobilization of the amino-functionalized MSCS on the immobilized QDs. Immobilization of the anti-citrinin antibody on the surface of the amino-functionalized MSCS was performed by Schiff-base mechanism. By using these three effective strategies, sensitivity of the designed nanobiosensor was incredibly enhanced as a very low limit of detection (up to 0.1 pM). The feasibility of this technique was tested by the detection of citrinin in the spiked human serum. Results showed that there was a linear correlation between the decreased fluorescence intensity of the Rho123 and increased fluorescence intensity of the QDs with increasing concentration of citrinin in the spiked samples in the range of 1–6 pM. According to obtained results, we conclude that this highly sensitive detection scheme is a easy, quick and impressive method that can be used in optical-based nanosensors. 相似文献
123.
Ahmad Mahmoudi Jan Zima Boris Kryštufek Jamshid Darvish Mansour Aliabadian 《Zoology in the Middle East.》2018,64(1):1-8
The distribution of C-heterochromatin and nucleolar organizer regions (NORs) was studied in three species of voles of the Microtus arvalis group in Iran: M. mystacinus, M. kermanensis, and M. transcaspicus. The C-banding pattern and NORs distribution were similar in M. mystacinus and M. kermanensis suggesting taxonomic proximity of these two species. At the same time, the karyotypes of M. mystacinus from Iran were different in C-banding pattern from the complements of conspecific 54-chromosome voles from Europe and other regions of Asia. The most distinct difference was in size of the distal C-positive block of heterochromatin on the X chromosome. In this respect M. mystacinus from Iran and M. kermanensis resembled M. transcaspicus. Small size of the distal C-positive heterochromatic block may be ancestral whereas larger size is derived. The X chromosome of M. transcaspicus can be derived from that of M. mystacinus and M. kermanensis by a large inversion or centromeric shift. 相似文献
124.
Hamid Mohammadi Mehrnaz Hatami Khatoon Feghezadeh Mansour Ghorbanpour 《Acta Physiologiae Plantarum》2018,40(4):69
Due to its wide industrial application, chromium (Cr) is known to be a critical environmental pollutant. Contamination of water and agricultural soil by Cr inhibits crop productivity and their physiological and biochemical processes. The objective of the current work was to investigate the effects of appropriate reducing agents such as EDTA, iron sulfate (Fe2+), and zerovalent nano iron (Fe0 nanoparticles) on growth and physiology of sunflower plants under Cr(VI) stress. Results showed that the Cr uptake increased by increasing the amount of EDTA, leading to a significant reduction in morphological and physiological parameters except for MDA and H2O2 contents. Treatment with Fe0 nanoparticles and Fe2+ reduced Cr concentration in root and shoot, increased root and shoot dry weight, plastid pigments (chlorophyll and carotenoids) and proline contents; however, the level of MDA and H2O2 decreased significantly. All parameters were affected by Fe2+ during the first week of sampling; however, Fe0 nanoparticles affected all traits until the end of the third sampling stage. A statistically significant and positive correlation was found between root Cr concentration and MDA and H2O2 seedlings treated with EDTA, Fe2+, and Fe0 grown under Cr stress. From the result of this study, it can be concluded that sunflower has the potential for accumulation of Cr as a heavy metal, and treatment with Fe0 nanoparticles to prevent Cr uptake is more effective than other employed treatments. 相似文献
125.
Maged P. Mansour John K. Volkman Anne E. Jackson Susan I. Blackburn 《Journal of phycology》1999,35(4):710-720
The fatty acid and sterol compositions of five species of marine dinoflagellates (Scrippsiella sp. Symbiodinium microadriaticum Freud, Gymnodinium sp., Gymnodinium sanguineum Hirasaki, and Fragilidium sp.) are reported. All contained the major fatty acids that are considered common in dinoflagellates, but the proportions were quite variable, and some species contained low contents of some polyunsaturated fatty acids. Concentration ranges for the major fatty acids were: 16:0 (9.0%–24.8%), 18:4(n-3) (2.5%–11.5%), 18:5(n-3) (7.0%–43.1%), 20:5(n-3) (EPA) (1.8%–20.9%), and 22:6(n-3) (DHA) (9.9%– 26.3%). Small amounts of novel very-long-chain highly unsaturated C28 fatty acids occurred in all species. Each dinoflagellate contained a complex mixture of 4-methyl sterols and 4-desmethyl sterols. Four species contained cholesterol, although the amounts were highly variable (from 0.2% of total sterols in Scrippsiella sp. to 45.6% in Fragilidium sp.). All but G. sanguineum contained the 4-methyl sterol dinosterol, and all species contained sterols lacking a double bond in the ring system (i.e. stanols); in Scrippsiella sp. cholestanol composed 24.3% of the total sterols. Other common features of the 4-methylsterol profiles were the presence of 23,24-dimethyl alkylation and unsaturation at Δ22 in the side chain. In Scrippsiella sp., four steroidal ketones were identified: cholestanone, dinosterone, 4α,23,24-trimethyl-5α-cholest-8(14)-en-3-one, and dinostanone. The structures of these corresponded to the major sterols in this species, suggesting that the sterols and steroidal ketones are biosynthetically linked. Steroidal ketones were not detected in the other species. Although fatty acid profiles can be used to distinguish among algal classes, they were not useful for differentiating among dinoflagellate species. In contrast, whereas some taxonomic groupings of dinoflagellates display similar sterol patterns, others, such as the gymnodinoids studied here, clearly do not. The combination of fatty acid, sterol, and steroidal ketone profiles may be useful complementary chemotaxonomic tools for distinguishing morphologically similar species. The identification of steroidal ketones supports earlier suggestions that certain dinoflagellates might be a significant source of such components in marine environments. 相似文献
126.
Atef A. H. Mansour Donald W. Mkay Jon Lien James C. Orr Joseph H. Banoub Nils Øien Garry Stenson 《Marine Mammal Science》2002,18(1):112-120
Measurement of progesterone concentration in blubber was developed as a method to detect pregnancy in minke whales. Progesterone was extracted and quantified from blubber samples of minke whale carcasses by radioimmunoassay. Results showed a highly significant difference (almost 60-fold) between blubber progesterone concentrations of anatomically determined pregnant females versus non-pregnant female or male carcasses. The results of the study suggest that the blubber progesterone concentrations might be used to determine pregnancy status in free-ranging whales. 相似文献
127.
Akram Khan Mansour Qurashi Kim Kwiatkowski Don Cates Henrique Rigatto 《Journal of applied physiology》2005,98(4):1171-1176
We measured the PCO2 apneic threshold in preterm and term infants. We hypothesized that, compared with adult subjects, the PCO2 apneic threshold in neonates is very close to the eupneic PCO2, likely facilitating the appearance of periodic breathing and apnea. In contrast with adults, who need to be artificially hyperventilated to switch from regular to periodic breathing, neonates do this spontaneously. We therefore measured the apneic threshold as the average alveolar PCO2 (PaCO2) of the last three breaths of regular breathing preceding the first apnea of an epoch of periodic breathing. We also measured the PaCO2 of the first three breaths of regular breathing after the last apnea of the same periodic breathing epoch. In preterm infants, eupneic PaCO2 was 38.6 +/- 1.4 Torr, the preperiodic PaCO2 apneic threshold was 37.3 +/- 1.4 Torr, and the postperiodic PaCO2 was 37.2 +/- 1.4 Torr. In term infants, the eupneic PaCO2 was 39.7 +/- 1.1 Torr, the preperiodic PaCO2 apneic threshold was 38.7 +/- 1.0 Torr, and the postperiodic value was 37.9 +/- 1.2 Torr. This means that the PaCO2 apneic thresholds were 1.3 +/- 0.1 and 1.0 +/- 0.2 Torr below eupneic PaCO2 in preterm and term infants, respectively. The transition from eupneic PaCO2 to PaCO2 apneic threshold preceding periodic breathing was accompanied by a minor and nonsignificant increase in ventilation, primarily related to a slight increase in frequency. The findings suggest that neonates breathe very close to their PCO2 apneic threshold, the overall average eupneic PCO2 being only 1.15 +/- 0.2 Torr (0.95-1.79, 95% confidence interval) above the apneic threshold. This value is much lower than that reported for adult subjects (3.5 +/- 0.4 Torr). We speculate that this closeness of eupneic and apneic PCO2 thresholds confers great vulnerability to the respiratory control system in neonates, because minor oscillations in breathing may bring eupneic PCO2 below threshold, causing apnea. 相似文献
128.
Essam Abdel-Salam Shaalan Deon Vahid Canyon Reinhold Muller Mohamed Wagdy Faried Younes Hoda Abdel-Wahab Abdel-Hamid Mansour 《Journal of vector ecology》2007,32(1):16-21
A twelve-month survey for mosquito predators was conducted in Townsville, Queensland, Australia, which is located in the arid tropics. The survey revealed the presence of five predaceous insects but only Anisops sp. (backswimmers) and Diplonychus sp. were common. Predatorial capacity and factors influencing this capacity were then assessed for adult Anisops sp. and adult and nymph stages of Diplonychus sp. against Culex annulirostris mosquito immatures under laboratory conditions. Predatorial capacity bioassays showed that adult Diplonychus sp. preyed upon both larval and pupal stages of Cx. annulirostris quite successfully. Nymphs of Diplonychus sp. proved to be more successful with smaller prey immatures, and Anisops sp adults did not prey successfully on any prey pupae. Increasing the foraging area and introducing aquatic vegetation significantly reduced the predatorial capacity of Diplonychus sp. nymphs, while only vegetation and not foraging area had a significant effect on adult Diplonychus sp. predation capacity. Overall, adult Diplonychus sp. proved to be a more efficient predator than Anisops sp., and field trials are now recommended to further assess the potential of Diplonychus sp. as a biocontrol agent. 相似文献
129.
Ariyo Shahin-jafari Mansour Bayat Mohammad Hassan Shahhosseiny Parviz Tajik Shahla Roudbar-mohammadi 《Saudi Journal of Biological Sciences》2016,23(3):426-433
Over the last decade, communication industries have witnessed a tremendous expansion, while, the biological effects of electromagnetic waves have not been fully elucidated. Current study aimed at evaluating the mutagenic effect of long-term exposure to 900-MHz radiation on alpha-Int1 gene sequences of Candida albicans. A standard 900 MHz radiation generator was used for radiation. 10 ml volumes from a stock suspension of C. albicans were transferred into 10 polystyrene tubes. Five tubes were exposed at 4 °C to a fixed magnitude of radiation with different time periods of 10, 70, 210, 350 and 490 h. The other 5 tubes were kept far enough from radiation. The samples underwent genomic DNA extraction. PCR amplification of alpha-Int1 gene sequence was done using one set of primers. PCR products were resolved using agarose gel electrophoresis and the nucleotide sequences were determined. All samples showed a clear electrophoretic band around 441 bp and further sequencing revealed the amplified DNA segments are related to alpha-Int1 gene of the yeast. No mutations in the gene were seen in radiation exposed samples. Long-term exposure of the yeast to mobile phone radiation under the above mentioned conditions had no mutagenic effect on alpha-Int1 gene sequence. 相似文献
130.
Mansour S. Alsaid Mostafa M. Ghorab Saleh I. Alqasoumi Maged S. Abdel-Kader 《Russian Journal of Bioorganic Chemistry》2016,42(5):567-573
A novel series of thiourea and carbamimidothioic acid derivatives was synthesized using natural alkaloid L-norephedrine as a starting material. Structures of the newly synthesized compounds were confirmed by analytical and spectral data. The synthesized compounds were evaluated in vitro for anticancer activity against the human breast (MCF-7), human liver (HEPG2), and human colon (HCT116) cancer cell lines. Best activity of the synthesized compounds was expressed against HEPG2, however, none of the compounds exceeded the IC50 of doxorubicin. The corresponding N-(1-(2-chloroacetoxy)-1-phenylpropan-2-yl)-N′-p-tolylcarbamimidothioic acid was the most potent compound and exhibited higher cytotoxic activity against the human colon cancer cell line (HCT116) when compared with the reference drug doxorubicin. Also, this compound was the most active against the MCF-7 cell line but less active than the positive control. 相似文献